Drive mechanism for rectilinear knitting machines



Dec. 29, 1970 v. JUNCU ETAL 3,550,399

DRIVE MECHANISM FOR RECTILINEAR KNITTING MACHlNES Filed Feb. 17, 1969 Attorney United States Patent O 3,550,399 DRIVE MECHANISM FOR RECTILINEAR KN ITTIN G MACHINES Virginia .luncu, Zsigmond Trk, and loan Petra, Cluj,

Rumania, assignors t Intreprinderea Industriala Metalurgica de Stat Metalul Rosu, Cluj, Rumania,

a corporation of Rumania Filed Feb. 17, 1969, Ser. No. 799,791 Int. Cl. D04b 7/00 U.S. Cl. 66--60 9 Claims ABSTRACT OF THE DISCLOSURE A transmission imparting reciprocating movement to the slide of a linear (straight) knitting machine, especially short-stroke slides of the type provided in rectilinear knitting machines for the production of the fingers of gloves and the like. The transmission includes a chain linked to a slide-controlling member and passing over a pair of rollers located at least in part below the bed of the knitting machine. Between these rollers along the lower reach of the chain, a link is provided for articulation to a rod connected to the eccentric of a y-wheel driven by a speed reducing transmission. The articulated member is guided linearly parallel to the bed of the machine and to a plane defined by the shaft axes of the sprocket `wheels about which the chain passes.

Our present invention relates to a transmission for converting rotary movement, e.g. the output of an electric motor, into rectilinear movement for control for a machine element; more particularly, the invention relates to the control of short-stroke, fiat-bed rectilinear knitting machines having a bank of tongue-type (latch) needles which are displaceable or which cooperate with fingers adapted to shift the yarn for the knitting of fabric, especially relatively narrow fabric strips of the type used in the manufacture of gloves.

While many types of knitting machines have been pro posed and various drives have been used with them, it has been found that difiiculties arise with rectilinear knitting machines of the flat-bed type using tongue or latch needles for the formation of bands of narrow widths, e.g. for knitting of the lingers of gloves and the like.

For example, wide-bed knitting machines may have a slide which controls the needles and/or the lingers cooperating therewith, as they are shifted along the bed, or reciprocated; the mechanism can include a crank or eccentric linked by a connecting rod with the slide. Some chain-type drives have been provided in this general category. In all cases, it has been found that these arrangements are unsuitable for short-stroke operations and for the reciprocaton of the slide or control members of rectilinear knitting machine having narrow structures or widths. In fact, it is difficult to mount existing mechanisms on such machines, to so simplify them as to'make them suitable for the smaller machines, and to limit the detrimental effect of inertia and play necessarily present in large drive mechanism.

It is therefore, the principal object of the present invention to provide an improved mechanism for transforming rotary movement of an electric motor, for instance, into linear reciprocating movement of a control element.

Another object of our invention is the provision of an improved reciprocating mechanism for a knitting machine.

Yet a further object of this invention is the provision of an improved mechanism or transmission for the dri-ve of a narrow-width knitting machine, e.g. for the manufacture of glove fingers and the like, which can be 3,550,399 Patented Dec. 29, 1970 mounted conveniently with respect to the knitting machine, which does not generate excessive inertia, vibration and impact on the machine bed, and which is accurate with a minimum amount of play and is of sufficient speed for the operation of such machines.

These objects and others which will become apparent hereinafter are attained in accordance `with the present invention, by providing a drive mechanism for a shortstroke rectilinear knitting machine of the type alluded to in German Pat. No. 615,800, with a chain arrangement in which a control member is connected to the slide or other reciprocated element of the knitting machine, this member being linked in an endless chain passing about a pair of sprockets which are rotatable about axes delining a plane parallel to the bed of the knitting machine and in the direction of reciprocaton of its control member.

The linked member or coupling member, by means of which the chain is connected to the controlled element of the knitting machine, is disposed as a link in the upper reach or pass of the chain which advantageously lies in a vertical plane. `Only this reach need appear above the knit-ting bed or table while the remainder of the chain may be disposed therebelow.

According to an important feature of this invention, the chain is reciprocated by a ywheel via an eccentric on the latter, the flywheel being driven through a speedreducing gear arrangement from an electrical motor or other source of primary motive power. The chain is connected with the eccentric via a connecting rod which is articulated or pivoted to the chain, preferably at a location directly opposite the coupling member in the median position of the latter in its reciprocating stroke.

The articulating arrangement can include a block connected in the chain along this other reach. The block, according to our invention, is guided upon a fixed rod or bar (fixed with respect to the axes of the sprocket, the ywheel and the knitting machine) which is parallel to the plane of the axes of the sprocket and the bed of the machine. The axis of this bar or rail may, in turn, be coplanar with the axis of the liywheel.

In realizing the instant invention, we have found that it is advantageous to provide the coupling block and the articulation block as links in the endless chain which thus may consist of a pair of chain sections hinged at the corresponding ends to the blocks and passing about the respective sprockets. The stroke of the coupling block is thus limited to the distance between the centers of the sprockets.

The above and other objects and features and advantages of the present invention will become more readily apparent from the following description, reference being made to the accompanying drawing, the sole ligure of ywhich is a diagram illustrating the present invention.

In the drawing, we show a transmission for driving a knitting machine with rectilinear reciprocating movement. The moving force for the transmission is an electric motor 11 having an output pulley 12 of the V-belt type whose belt 13 drives the input pulley 14 of a speed-reducing gear arrangement 15. The shaft 16 of pulley 14 is keyed to a pinion gear 17 mounted between the support plates 18 (one shown) of the transmission on the outside of which a flywheel 1 can be seen.

The ilywheel 1 is keyed to the shaft 19 which is driven by a large diameter gear 20` meshing with the pinion 17 and forming therewith a speed-reducing gear transmission whose reduction ratio is the ratio of the number of teeth of gear 20 to the number ofI teeth of gear 17. The flywheel 1 forms an eccentric or crank with a crankpin 2 which is entrained by the iiywheel 1 in its rotary movement in the clockwise sense (arrow A), the gear 17 being rotated in the counterclockwise sense as represented by the arrows B and C. The crank pin 2 is thus eccentric with respect to the axis 21 of shaft 19 and is shown in its lower dead center position as represented at II".

A rigid connecting rod 3 is hinged at the crank pin 2 to the ywheel 1 and is also pivotally attached at 22 to a link block 4. The latter has an internal bore 23 of rectangular cross section which receives a guide bar anchored at 5a and 5b to a support structure generally represented at 24 and constituted by the base of the machine. The block 4 can be reciprocated on the bar 5 between its extreme positions represented at I and III through the intermediate position II.

The block 4 is connected in an endless chain passing around sprockets 8 and 9 which lie in a vertical plane corresponding to the plane of the paper of the drawing and are journaled on the support 24 via the respective shafts 25 and 26. The axes 27 and 28 of these shafts extend horizontally (i.e. perpendicular to the plane of the paper) and define a horizontal axial plane P which is parallel and below the bed 29 of the knitting machine which may be of the type described in U.S. Nos. 3,102,403; 3,102,404; 3,153,922 and the patents therein cited or of the same class. The plane P is parallel to the plane P of the lower reach of the chain and the axes of bar 5, the plane P also constituting the plane of the axis 21.

Along the upper reach of the chain, above the bed or table of the knitting machine, there is." provided a link member which can be coupled with the Sledge, slide or carriage 30 of the knitting machine K for reciprocating movement of the latter to operate the latch or tongue needles and/ or the thread guides co-operating therewith as is well known in the art in connection with the aforedescribed type of machine. The endless chain arrangement includes a pair of chain sections 6 and 7, respectively passing around the sprockets 8 and 9. Member 10 is provided with a notch 31 to receive the connecting rod 32 by means of which the carriage 30 is driven.

The chain sections 6 and 7 have corresponding end links 6a and 7a pivotally connected to member 10 and, along the lower reach, end links 6b and 7b pivotally connected to the block 4. Of the mechanism, only minor portions of the wheels 8 and 9, the upper reach of the chain and link member 10 lie above the machine table While the balance of the transmission, including this reducing gear is located below this table.

As the `iiywheel 1 rotates from its lower dead center position II into position I, the block 4 is shifted to its position I and entrains the sprocket wheels 8 and 9 in the clockwise sense to carry the link member 10 into its extreme position I with a corresponding displacement of the knitting machine carriage and operation of the row of knitting needles forming a narrow knit band, e.g. for gloves and the like. As the ywheel 1 continues to its dead center position, block 4 is returned to its intermediate position II, thereby bringing the link member 10 into its intermediate position II. Further rotation of the flywheel carries the crank pin 2 to an extreme position on the righthand side of the axis 21 and thereby draws the block 4 to the right (III) to shift the link member 10 to the left III with a similar movement of the knitting machine carriage. This transmission is of simplified con- 4 struction, is of high speed, enables positioning of the transmission below the knitting table and restricts vibration of the machine.

The improvement described and illustrated is believed to admit of many modifications within the ability of persons skilled in the art, all such modifications being considered within the spirit and scope of the invention except as limited by the appended claims.

We claim:

1. In a combination with a rectilinear knitting machine having a linearly reciprocable carriage, a transmission for reciprocating said carriage, said transmission comprising a drive motor having a rotary output; speed-reducing-gear means conected to said output of said motor and driven thereby; a flywheel on said speed-reducing-gear means and rotatable thereby; endless-chain means eccentrically connected to said flywheel at one reach of the chain for reciprocation; and means connecting said carriage with the other reach of said chamber.

2. The combination defined in claim 1 wherein said endless-chain means includes a guide block shiftable as part of said one reach, said transmission further comprising 'a guide bar slidably engaging said guide block and concentrating same to linear movement, and a pair of sprocket wheels in spaced-apart relationship having respective axes of rotation defining a plane parallel to said bar, said chain passing around said sprocket wheels, said rod being pivotally connected to said block.

3. The combination defined in claim 2 wherein the means for connecting said chain with said carriage includes a link member forming part of said other reach.

4. The combination defined in claim 3 wherein said link member is formed with a notch adapted to receive an actuating rod connecting with said carriage.

5. The combination defined in claim 3 wherein said chain includes a pair of chain sections respectively connected to said member and said block and passing around the respective wheel.

6. The combination defined in claim 5 wherein said flywheel has an axis of rotation lying substantially in the plane of said bar.

7. The combination defined in claim S wherein said knitting machine has a table; said link member lies above said table; and said block, said rod and said speedreducing means lie below said table.

8. The combination defined in claim 7 wherein said flywheel has a crankpin and said rod is swinga-bly mounted on said crankpin.

9. The combination defined in claim 8 wherein said sprocket wheels and said chain lie in a plane perpendicular to the aforementioned planes.

References Cited UNITED STATES PATENTS RONALD FELDBAUM, Primary Examiner U.S. Cl. X.R. 66--64 

